Hoisting drum safety control



March 20, 1951 F. R. SPRIGGS HOISTING DRUM SAFETY CONTROL 2 Sheets-Sheet 1 ,Filed Jan. 10, 1950 FIG. 5

INVENTOR FLOYD R. SPRIGGS ATTORNEYS March 20, 1951 F. R. SPRIGGS 2,545,594

HOISTING DRUM SAFETY CONTROL Filed Jan. 10, 1950 v 2 Sheets-Sheet 2 FIG. 2

FIG. 8 30 FIG. 4

INVENTOR FLOYD R. SPRIGGS Patented Mar. 20, 1951 Floyd R. Spriggs, Beaver Dam, Ky.

ApplicationJanuary 10, 1950, Serial No. 137,683

4 Claims.

This invention relates to hoisting drum controls, and more particularly to a safety control effective to automatically stop the drum in the event of power failure or failure of the hoisting drum operating mechanism.

It is among the objects of the invention to provide a hoisting drum safety control for the holsting drums of lifting and excavating machines, such as the large power shovels used in strip. coal mining, which will automatically stop the drum in the event of power failure or failure of the drum operating mechanism to prevent dropping of the shovel or other device Operated by the drum, which can be applied to an existing hoisting drum operating assembly with no material modification of the existing structure and'does not interfere in any way with the normal operation of the hoisting drum, and which safety control includes a minimum number of parts of simple and durable construction, is economical to manufacture and easy to install, and is highly effective in preventing damage to the equipment to which it is applied.

Other objects and advantages will become apparent from a consideration of the following description and the appendedclaims in conjunction with the accompanying drawings wherein:

Figure 1 is an end elevation of a hoisting drum and operating mechanism therefor with safety control means illustrative of, the invention operatively applied thereto, a portion of the drum operating mechanism being broken away to simplify the illustration;

Figure 2 is a top plan view of the drum and operating mechanism illustrated in Figure 1, por tions being broken away and shown in cross section to better illustrate the construction of the device;. g

Figure 3 is a longitudinal cross section of a brake operating component of the assembly illustrated in Figure 1 and is taken substantially on the line 3-3 of Figure 1;.

Figure 4 is a medialv cross sectional view of the two electromagnetic valves illustrated in Figure c Figure 5' is a cross sectional view on an enlarged scale on the line 55 of Figure 1;.

Figure 6 is a cross section on the line t'6 of V valve on the line 8-3 of Figure 1.

With continued reference to the drawings and particularly to Figures 1 and 2, the numeral H! designates a horizontally disposed hoisting drum shaft rotatably journaled in suitable bearings, not illustrated, carried by the fixed frame of the machine in which the hoisting drum is installed. A cable winding hoisting drum or spool II is journaled on the shaft and is externally threaded to provide cable receiving grooves I2 in which a cable is received as it is wound onto the drum, The drum cable, not illustrated, is connected to a device to be raised and lowered by the winding drum, such as an elevator, a power shovel bucket or a crane boom.

A double drive gear [3 having peripheral gear teeth of herringbone formation is secured on the shaft ID at one end of the drum H and this gear is driven by one or more power operated devices, such as electric motors having on their shafts spur gears meshing with the teeth of the gear 13.

An annular clutch element or drum is secured to the cable drum l l at the end of the latter adjacent the gear l3 and is substantially coaxial with the cable drum and the shaft S0. A complementary clutch element or band l5 peripherally surrounds the drum carried brake element I4 and is secured at its ends to the gear l3 by the anchor pins l6 and H which extend through and are journaled in the spokes or web It of the gear. The anchor pin it is connected to one end of the clutch band' 15 by an adjustable connecting assembly [-9 and the pin I1 is connected to the other end of the clutch band by an adjustable connecting assembly Zll. The pin I! has an eccentric cylinder 2| rotatably received in the connecting assembly 20 so that when the pin or shaft I I is rotated in one direction the band I5 will be tightened around the drum hi to provide a torque transmitting connection between the gear l3 and the drum H and when the pin I1 is rotated in the opposite direction the clutch band will be released from the clutch drum to render the cable drum 8 l freely rotatable relative to the gear [3 and shaft II)".

An arm 22 is secured at one. end to the pin [=1 at the side of the gear opposite the clutch elements M and- !5 and this arm carries a crank 23 on its other end.

A flanged structure 24 is secured on the gear I3 between the hub 25 and the rim of the gear and includes a cylinder 26. A piston is reciprocable in the cylinder 26 and a piston rod 21 extends from the piston through the end of the cylinder adjacent the arm 22 and is connected to the crank 23 by a link 28. An inlet fitting 29 is' secured to the structure 24- at the end of the latter remote from the arm 22 and communicates with the interior of the cylinder 25. A conduit extends from a bore in the shaft H) to the inlet fitting 29 for supplying air under pressure to the cylinder. When compressed air is supplied to the cylinder the arm 22 is moved by the piston and piston rod 2'! in a direction to contract the clutch band l5 thereby providing a torque transmitting connectionbetween the gear and the cable drum H so that the cable drum will be rotated by the power operated drivin mean engaging the gear.

A source of compressed air 3|, such as an air compressing pump, is provided and conduit means 32 and 33 connect this source of compressed air to the bore in the shaft l9 and a manually controlled solenoid valve 34 is connected into the conduit means 32 and is o arranged,

as particularly illustrated in Figure 4, that when the power to the solenoid is cut off by opening a suitable switch or by failure of power to the solenoid the valve is positioned to connect the compressed air source 3| to the cylinder 26 to engage the clutch and when the solenoid circuit is completed by closing the manually operated switch the valve is positioned to cut off the supply of air to the cylinder 26 and vent the cylinder so that the clutch will be released. When the cylinder is vented the arm 22 is moved in a clutch releasing direction by a tension spring 35 connected at one end to the arm 22 and at its opposite end to a lug formation 36 onthe flanged structure 24.

A brake element or drum 3'! is secured to the cable drum H at the end of the drum opposite the clutch element I4 and is disposed coaxially of the drum. A complementary brake element or band 38 surrounds the brake drum 3'! and a brake actuating lever 39 is pivotally mounted on a fixed support 49 and pivotally connected at one end to one end of the brake band 38, as indicated at M. The other end of the brake band 38 is connected to the pin 42 which connects the lever '33 to the fixed support 49 by a clip or link 43. A brake cylinder 44 is mounted on a fixed support and includes a piston 45. A piston rod 45 extends from the piston through one end of the brake cylinder and is secured by a link 4'! to the end of the lever 39 opposite the end of the lever connected to the brake band. A spring abutment 38 is secured on the piston rod 45 within the cylinder 44 and a heavy compression spring 49 surrounds the piston rod between the abutment 48 and the end of the cylinder adjacent the lever 39 and is effective to resiliently move the piston rod 45 in a direction to contract the brake band 38 upon the brake drum 3'! and apply the brake.

A conduit 59 extends from a T-connection 5| with the conduit 32 to the end of the brake cylinder 44 remote from the lever 39 for the application of fluid under pressure into the space between the piston 45 and the end of the brake cylinder to which the conduit 50 is connected to move the piston 45 in a direction to release the brake.

A solenoid valve 52 is connected into the conduit 5i} and is controlled by a manually operated switch, not illustrated. This valve 52 is so arranged that when power is applied to its solenoid it admits fluid under pressure to the cylinder it to release the brake and when its solenoid is de-energized, either by opening the associated switch or by power failure, it closes off the side of the conduit 50 adjacent the T-fittin 5| and thence the brake cylinder so that the spring 49 is rendered effective to apply the brake.

With this arrangement the solenoid valves 34 and 52 can be manually controlled to release the brake and engage the clutch, to release the clutch and simultaneously engage the brake or to engage both the clutch and the brake in the event of power failure to the machine.

The above described construction is all old and well known except for the particular arrangement of the solenoid valves 34 and 52 and the conduits 32, 33 and which arrangement constitutes a part of the present invention for providing an automatic safety control for the hoisting drum. The invention further embodies a trip valve, generally indicated at 53, mounted on the gear I3 and connected by a conduit 54 and T-fitting 55 to the conduit 39, a check valve 55 interposed between the T-fitting 55 and the inlet fitting 29 for the cylinder 25 and a check valve 51 interposed in the conduit 59 which leads from the solenoid valve 52 to the brake cylinder 44.

The trip valve 63 comprises a flanged body 58 which includes a hollow valve body 59 and is mounted on the gear l3 adjacent the end of the piston rod 2? projecting from the cylinder 26 of the body 24. The conduit 54 is connected into one end of the hollow valve body 59 and the other end of the valve body is open and internally screw threaded. A nut 50 having a bore therethrough is threaded into the open end of the valve body and a poppet valve 6| has its stem 62 slidably mounted in the nut and its head 63 cooperating with a beveled valve seat 54 formed in the valve body. A vent opening 65 is provided in the valve body at the side of the seat 64 opposite the end of the body to which the conduit 54 is connected. 7

An arm 66 projects from the valve body 59 at the end thereof receiving the nut 6|] in a direction away from the end of the valve body receiving the conduit 54 and an apertured lug 6! is provided on the opposite side of the valve body. A lever 58 is pivotally connected at one end to t -e lug 61 and extends in a direction away from the end of the valve body receiving the conduit 54 and intermediate its length this lever is provided with an opening 69 having a detent formation 73 therein. A bar I! is pivotally connected at one end to the arm 66 at the end of the arm 66 ope posite that connected to the valve body 53 and this bar extends through the opening 59 in the arm or lever 68 and has a shallow notch in which the detent 19 is seated. The bar H overlies the adjacent end of the valve stem 62 and is provided with a screw threaded aperture which is in longitudinal alignment with the valve stem. An adjusting screw 12 is threaded through the aperture in the bar H and bears at one end on the adjacent end of the valve stem. The lever 68 is provided at its end opposite that pivotally connected to the valve body with a screw threaded aperture and a stud bolt 13 is threaded through this aperture and secured in adjusted position by a lock nut 14.

A projection 15 is provided on the end of the piston rod 21 connected to the link 28 and the trip valve 53 is so mounted on the gear that one end of the bolt 13 is in alignment with the projection E5 in the direction of movement of the piston rod and is normally spaced from this projection.

i 5. The. distance between. the. projection. 15. and. adiacent end of the bolt: .3 is: such that. the. piston rod 2:]: can. mov to: en a e the clutch without. contactin the bol but, if. th arm; .2:, h clutch band 4.5 or some. other part of: the clutch operate n mechanism breaks. the piston rod. will. mov an additional: distance and will; contact the bolt 3 a d; m r the detent Ill beyond. the adjacent and i th bar M... This release of; the. a Tl will release the valve 61 from its seat fi l'so that the conduit 54 will be directly connected. h the vent. opening 65. inv the. valve. body;v This. w l immediatelvvent the conduits 3B... 33 and d and free the brake spring: 4a to en age the brake and hold the cable drum against:- mcvoment. therebyprecluding dropping of a. shovel buck t. e evator or other device operated by the cabl drum. when the two solenoid valves 34 and. 52 are in position as illustrated in Figure wlth the electric power on but. with the solenoid it of the valve 3,! de-energized by the opening of a menually operated switch connected into itsv energizingcircuit, the fluid under pressure, such as compressed air, flows from the compressor 3| to. the value. 3.4 and through this valve and the condmt 3,2 to; the T fitting. 5|: and. the conduits 3-3 and 5d,. the solenoid 1-]: of the valvev .52 bein en r i ed This supplies air under pressure to the clut h op ratin cylinder 26 and the brake. cylinder #4 s multaneousl en aging: the clutch and releasins: the brake. Under these. conditions the drum l-lwill be. rotated by the gear 1 for liitiug the devi e op rated bythe drum. When it is; desired to. stop the drum the solenoid 1-6 is energized and the solenoid. 71 is. simultaneously die-energized whe eupon. the valve. 34 will vent the condui 32- and the c nduits t3 and 30. re as h t h and the. v lve 52 will. vent the condui 59. free! the: the spring. 4.9. to enga e the brake.

the event of. power failure to the machine both. solenoids 16. and 11 will be (lo-ene giz the val were n. drum rotating. position, as illustrated. inFisur a the time, of power failare the valve 34 will remain in the. same osition maintaining a. Supply of. compressed air to the clutch cylinder to keep the clutch engaged while the valve 52 will move to its venting; position to also, engage the brake. the clutch and brake to: 581211.161 holding the drum against rotation during the. time he power is off- Gonnecting he. conduit 3.3 leadin to the. clutch opera ing cylinder between. the two. valves 34 and 52 is an. improvement of th pr sent, in: vention. and, with this arrangement, if. the trip valve. 53 is. tr pped. to ventv the. brake cylinder and appl he r e upon failure of some. part oi the clutch opera ing mechanism. the clutch valve can. e immediately closed by ener iz solenoid 6- and this will out. 01f the sup ly of; c mpressed air from. the compressed air source 31 so. tha the compressed air in the. reservoir tank will not. bev exhausted and the. supply of compressed air to the broken clutch operating mechanism will be discontinued.

The check valve 5 fully open when air is flowing through the conduit 30- to the inlet. fit: tin 2.9; of the. clutch. operating mechanism so that flow of air in this direction. is. not substantially obs ruc ed but: provi es a restriction to th flow oi in he opposite. direction. The check valve 15.! pr v des for a substan ially unr stricted flow oi; air from. the brake cylinder 44 through the conduit 50 bu res r ts the. flow of. air h lml he conduit 50. to the brake cyl nder; With this arrangement, when the valves 34 and 52 are eperatedto. release the clutch. and engage the brake... the. brake. s ring 49. will be. immediately freed to engage the brake. but the disengagement of the clutch, will be slightly 176- tarded so. that the clutch will be. held. in eneas ment until the b ake is f lly nga d thus precluding any free period for drum rotationbetween release of..the. clutch, and en agement of. he brake. Qu the. oth r hand, wh n t l e 34. and 52 are operated to release the,v brake and engage the clutch the free flow o a r to the clutch operating cylinder will quickly engage thev clutch. but he restricted now of air to the brake cylinder will slight y r tard th releas of t e brake. so th t. the. clutch will be fully engaged before the brake is released.

If the supply of compressed air or other opcratin fluid. u der pressure should suddenly fail by breakage 0;. any one of the conduits or failure of. the compressor while the drum is being driven, the valve 5.6 would retard the. release of the clutch. until the. brake was fully engaged by the spring 49.. to avoid the possibility of dropping the shovel or elevator under these conditions.

The two check valve 5 and. m e. o any desired. construc ion but. as s a ed. h valve. 56 comprises a hollow valve body having a tapered, annular valve, seat 8 1 formed intermediate the length thereoi and having one end internally screw threaded to, receive the correponding end; o the c duit 0- At s pp s e end. the body 80 is recessed and externally screw threaded and a second hollow valve y 82 as an internally screw threaded counterborecl end threaded onto the recessed end of the body 80..

At, its other end the body/7 22'. is internally screw hreaded to receive the co spond n en f the conduit 30. and an apertured guide 83 within thebody .82. slidably supports the stem 84 of a poppet valvev 85 having a head 86" engageable with the valve seat 8| to close the valve. A light spring 8] surrounds the valve stem between the guide 83 and the head 86 and urgesthe valve head into seating engagement with the seat 81. A bleed opening 88 extends through the valve head to permit the restricted passage, of air through the check valve when the valve, is closed.

The valve 51 is similar in construction comprising two hollow valve bodies 90 and 9| similar tothe bodies 8| and 82 of the valve 56, a poppet type valve 92' engageable with a seat in the body 90 and having a bleed opening 93 through its head and a spring 94 resiliently urging the valve head into seating engagement with the valve seat in the body 90 The present safety control thus comprise three changes or additions to the existing drum control structure including the. rearrangement of theairsupply conduit to the clutch operating mechanism in relation to the solenoid operated valves 34- and. 52 the provision of the check valves '56. and 5] in the conduits supply-1 ing compressed air to. the, clutch operating mechanism and to the brake operating mechanism and the. trip valve, 53, operated by thev clutch operating mechanism in. the event of breakage of any of the; clutch operating. parts. a The. invention. may be embodied. in other specificf rms; Without depa in ro e p rit or essential characteristic thereo The p s..- ent embodiment-j is, therefore, to be.- considered in all respects: as illustrative and, not restrictive, the scene th in n ion b n n ica e b the appended claims rather thanby the foreof the claims are, therefore, intended to be embraced therein.

What is claimed is:

1. In combination with a cable drum and operating assembly therefor including a shaft, a drum on said shaft, a power driven gear on said shaft at one end of said drum, a clutch element carried by said drum, a clutch element carried by said gear and engageable with the drum carried clutch element to provide a torque transmitting connection between said gear and said drum, a fluid pressure operated expansible chamber device carried by said gear and connected to the gear carried clutch element to engage the gear carried element with the drum carried element, a brake element carried by said drum, a complementary brake element fixed relative to the drum carried brake element, a spring connected to the relatively fixed brake element resiliently urging the latter into braking engagement with said drum carried brake element, a fluid operated expansible chamber device connected to said relatively fixed brake element for releasing the latter from said drum carried brake element against the force of said spring, a source of fluid under pressure, conduit means connecting said source of fluid under pressure to said expansible chamber devices for simultaneously engaging said clutch elements and releasing said brake elements by the application. of fluid under pressure to both of said expansible chamber devices, manually controlled valve means in said conduit means for cutting ofi the supply of fiuid under pressure to said expansible chamber devices and venting said devices to simultaneously release said clutch elements and engage said brake elements, a trip. valve mounted on said gear adjacent said gear carried expansible chamber device and connected into said conduit means to vent said expansible chamber device connected to said relatively fixed brake element when said trip valve is opened to thereby release said spring to engage said brake elements, said trip valve being opened by the gear carried expansible chamber device when the latter moves beyond its normal clutch element engaging position incident to failure of said clutch elements to drivingly engage.

2. In combination with a cable drum and operating assembly therefor including a shaft, a

drum on said shaft, a power driven gear on said shaft at one end of said drum, a clutch element carried by said drum, a clutch element carried by said gear and engageable with the drum carried element to provide a torque transmitting connection between said gear and said drum, a fiuid pressure operated expansible chamber device carried by said gear and connected to the gear carried clutch element to engage the gear carried element with the drum carried element, a brake element carried by said drum, a complern-entary brake element fixed relative to said drum carried brake element, a spring connected to the relatively fixed brake element resiliently urging the latter into braking engagement with said drum carried brake element, a fluid operated expansible chamber device connected to said relatively fixed brake element for releasing the latter from said drum carried brake element against the force of said spring, a source of fluid under pressure, a first manually controlled valve connected to said source of fluid under pressure, a first conduitconnecting said valve to the expansible chamber device'ca'rried by said gear, said first manually controlled valve having one operative position in which it connects said source of pressure withthe gear carried ex-i' pansible chamber device and another operative position in which it cuts off said source of air under pressure and vents said gear carried expansible chamber device, a second manually controlled valve, a second conduit connecting said second manually controlled valve to said first mentioned conduit, and a third conduit connecting said second manually controlled valve to said expansible chamber device connected to said relatively fixed brake element, said second manually controlled valve having two operative positions in one of which it connects saidfirst mentioned conduit to said expansible chamber device connected to said relatively fixed brake element and in the other of which itclo'ses off said second conduit and vents said expansible chamber device connected to said relatively fixed brake element.

3. In combination with a cable drum and operating assembly therefor including a shaft, a drum on said shaft, a power driven gear on said shaft at one end of said drum, a'clutch element carried by said drum, a clutch element carried by said gear and engageable with the drum carried element to provide a torque transmitting connection between said gear and said drum, a

fluid pressure operated expansible chamber device carried by said gear and connected to the gear carried clutch element to engage the gear carried element with the drum carried element, a brake element carried by said drum, a complementary brake element fixed relative to said drum carried brake element, a spring connected to the relatively fixed brake element resiliently urging the latter into braking engagement with said drum carried brake element, a fluid operated expansible chamber device connected to said rela tively fixed brake element for releasing the latter from said drum carried brake element against the force of said spring, a source of fluid under pressure, a first manually controlled valve connected to said source of fluid under pressure, a first conduit connecting said valve to the expansible chamber device carried by said gear, said first manually controlled valve having one operative-position in which it connects said source of pressure with the gear carried expansible chamber device and another operative position in which it cuts ofi said source of fluid under pressure and vents said gear carried expansible charnloer device, a second manually controlled valve, a second conduit connecting said second manually controlled valve to said first mentioned conduit, a third conduit connecting said second manually controlled valve to said expansible chamberdevice connected to said relatively fixed brake ele ment, said second manually controlled valvehaving two operative positions in one of which it connects said first mentioned conduit to said expansible chamber device connected to said relatively fixed brake element and in the other of which it closes off said second conduit and vents said expansible chamber device connected to said relatively fixed brake element, a check valve in said first mentioned conduit adjacent said gear carried expansible chamber device arranged to provide a substantially unrestricted flow of fluid to the associated expansible chamber device and a restricted flow of fluid away from the associated expansible chamber device, and a second check valve in said third conduit adjacent said expansible chamber device connected to said relatively fixed brake element and arranged to provide a substantially unrestricted flow of fluid away from the associated expansible chamber device and a restricted flow of fluid to the associated expansible chamber device.

4. In combination with a cable drum and operating assembly therefor including a shaft, a drum on said shaft, a power driven gear on said shaft at one end of said drum, a clutch element carried by said drum, a complementary clutch element carried by said gearand engageable with the drum carried clutch element to provide a torque transmitting connection between said gear and said drum, a first fluid pressure operated expansible chamber device carried by said gear and connected to the gear carried clutch element vto engage the gear carried clutch element with the drum carried element, a brake element carried by said drum, a complementary brake element fixed relative to the drum carried brake element, a spring connected to the fixed brake element resiliently urging the latter into braking engagement with said drum carried brake element, a second fluid pressure operated expansible chamber device connected to said fixed brake element for releasing the latter from said drum carried brake element against the force of said spring, a source of fluid under pressure, a first conduit connecting said source of fluid under pressure to said second expansible chamber device, two manually controlled valves connected into said first conduit at spaced apart locations therealong and each having one operative position in which it continues said conduit and another operative position in which it interrupts said conduit and vents the portion of the conduit at the side of the valve remote from said source of fluid under pressure, a first check valve in said first conduit between said second expansible chamber device and the manually controlled valve adjacent thereto, said first check valve being operative to provide a substantially unrestricted flow of fluid away from said second expansible chamber device and a restricted flow of fluid to the latter, a second conduit connecting said first conduit between said manually controlled valves to said first expansible chamber device, a trip valve mounted on said gear adjacent said gear carried expansible chamber device, a third conduit connecting said second conduit to said trip valve, said trip valve being operated by movement of said first expansible chamber device beyond its normal clutch element engaging position upon failure of said clutch elements to engage to vent said second FLOYD R. SPRIGGS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,543,889 Wickes June 30, 1925 1,560,984 Gorbutt Nov. 10, 1925 2,279,597 Selmer Apr. 14, 1942 

